The Vibroplex Original currently ships with the No. 401 (one ounce) weight. Does anyone knowthe approximate speed ranges of the key with, respectively,

The No. 401 (large) weight?

The No. 402 (4/5 ounce - medium) weight?

The No. 403 (2/5 ounce - small) weight?

You got no answer.

Did you not get math and physics in school?

Long, long, very long time ago, but _I_remember some basics.

K=m.a . A force K on a mass m yields an acceleration a.

s=K.c A force K on a (vibroplex spring) yields a displacement sc is a constant in your bug.

Now when you release the mass it starts swinging. As you know that means a harmonic movement. So the pendulumas function of the time has the position s(t)=sin (wt) with w =2.pi.f and f the (dit)frequency.the speed is the first derivative so v(t)=w.cos(wt)the acceleration is the first derivative of the speed hence a(t)=-w.w.sin(wt)

I have only a large weight and a small one but here is what I measured this morning:Large weight fastest: 30 WPM.Large weight slowest: 22 WPM

Small weight fastest: 41 WPMSmall weight slowest: 28 ½ WPM.

The Vibroplex is an Original Standard, new three weeks ago; serial # 402499. I used Audacity software and measured the interval between the start of the second dit and the start of the sixth dit, divided by four, took the reciprocal, and multiplied by 2.4.I certainly would not take these numbers to the bank but this is what I got. It’s my story and I’m sticking to it! I’m sure there will be criticism and critique regarding this. There always is. Fine.

The low end range of the bug with the stock large weight is approx 20 WPM. The bug was built as a high-speed device and it's stock range is approx 20-40 WPM overall with the large weight.

You can add more weight to slow it down some - we sell a device though specifically for that purpose called the Vari-Speed. Take the weight off, put the Vari-Speed on, then attach the stock weight to the Vari-Speed - low end 13 WPM or so.

I used Audacity software and measured the interval between the start of the second dit and the start of the sixth dit, divided by four, took the reciprocal, and multiplied by 2.4.I certainly would not take these numbers to the bank but this is what I got. It’s my story and I’m sticking to it! I’m sure there will be criticism and critique regarding this. There always is. Fine.

The low end range of the bug with the stock large weight is approx 20 WPM. The bug was built as a high-speed device and it's stock range is approx 20-40 WPM overall with the large weight.

You can add more weight to slow it down some - we sell a device though specifically for that purpose called the Vari-Speed. Take the weight off, put the Vari-Speed on, then attach the stock weight to the Vari-Speed - low end 13 WPM or so.

O yes.

Salesman talk. Kind of male cow manure like they are used to produce in order to transfer funds from your pocket to their pocket.

Usually successful.

I watched a bug design with separate springs for dots and dashes and the device is accompanied with a spring force measurement device in order to equalize the forces as good as possible.

Amazing.

Just use one spring when you think the forces has to be equal.

LESS then one and a half is the speed range, just as measured accurately by W0WCA.

as function of the time has the position s(t)=sin (wt) with w =2.pi.f and f the (dit)frequency.the speed is the first derivative so v(t)=w.cos(wt)the acceleration is the first derivative of the speed hence a(t)=-w.w.sin(wt)s(t)=sin wts(t)=-c.m.w.w.sin(wt)Hence c.m.w.w=-1

Bob, don't you need to factor in a correction for atmospheric pressure and the Coriolis effect?

Bob, don't you need to factor in a correction for atmospheric pressure and the Coriolis effect?

Hi

May be when the pendulum top is moving in an elliptic trace. You can even find out whether you are in the northern or southern hemisphere, when the back move of the pendulum is the upper of or the lower trace of the elliptical

Very roughly, something on the order of 20 - 40 wpm with the standard weight, as already said. That's a typical range of speeds, the exact range (if there is such a thing) will depend on your adjustment of the bug. Lots of 'play' in that. - Paul

If you happen to have an oscilloscope at your station that's a good way to check the speed/timing as well.

Also, I don't know if this is still an issue or not, but over the decades, Vibroplex would go through various "lots" of mainspring stock and the thickness/stiffness would vary. Sometimes quite a bit. If you have, say, a 1967 bug and a 1950 and a 2005, the same weight on all three could result in an entirely different range of speeds on each of the three. So the best thing to do is to have plenty of all three weights! :-)

I used Audacity software and measured the interval between the start of the second dit and the start of the sixth dit, divided by four, took the reciprocal, and multiplied by 2.4.I certainly would not take these numbers to the bank but this is what I got. It’s my story and I’m sticking to it! I’m sure there will be criticism and critique regarding this. There always is. Fine.

If you happen to have an oscilloscope at your station that's a good way to check the speed/timing as well.

Also, I don't know if this is still an issue or not, but over the decades, Vibroplex would go through various "lots" of mainspring stock and the thickness/stiffness would vary. Sometimes quite a bit. If you have, say, a 1967 bug and a 1950 and a 2005, the same weight on all three could result in an entirely different range of speeds on each of the three. So the best thing to do is to have plenty of all three weights! :-)

73

Tom AE5I

Good remark Tom. So sloppy handling of customers to sell a product that is supposed to be stable over time.

The guy that wrote that his bug as approximately 20 to 40 wpm has 50% tolerance build in his approximation because W0WCA measured it to be in a reliable described way to be 20 to 30 0ne and a half range. However when you sent 30 it feels good to be able to say you sent 40. So believe what you make feel you good. The adagium of religions, I suppose so.

But the idea fertilized by advertisements that you buy a real vibroplex and have the same feeling during transmitting as the guys on ships airplanes and railroads 60 years ago is hence a lie.

It may be that both W5LZ and W0WCA are correct. I notice that the dot speed can be varied quite a bit simply by adjusting the tension on the Dot Spring (hairpin). To achieve the slowest dot rate with the weight as far out on the end of the bar as it will go, the Dot Contact screw must be backed out almost to the point where the Dot Contact doesn't make contact with the contact on the Dot Spring when the pendulum is at rest.

W0WCA did not mention whether he varied the Dot Spring tension as well as moving the weight when he made his measurements, but W5LZ may be referring to this when he said: "Very roughly, something on the order of 20 - 40 wpm with the standard weight, as already said. That's a typical range of speeds, the exact range (if there is such a thing) will depend on your adjustment of the bug. Lots of 'play' in that."

I have only a large weight and a small one but here is what I measured this morning:Large weight fastest: 30 WPM.Large weight slowest: 22 WPM

Small weight fastest: 41 WPMSmall weight slowest: 28 ½ WPM.

The Vibroplex is an Original Standard, new three weeks ago; serial # 402499.

I agree with the figures above with an Original Standard. However, different keys react differently to weights. For example, the Blue Racer runs from 23WPM with a big weight up to 43-44 WPM. The lightining (with its square weight) ranges from 20WPM to 40WPM, but the lightning with Chrome base, surprisingly, is somewhat slower (16-17WPM up to 33-35 WPM).73 Carlo IK0YGJ

... not an easy question ...My everyday key is a paddle, however when I find a slower station (around 15-18 WPM) I go for the straight key. But then, if I listen a bug I cannot resist and plug a bug myself. However, some very rare stations use the sideswiper and ... I go with it.I would say that my key usage is 70% time paddle, 20% bug. 5% straight, 5% sideswiper.

More or less.73 Carlo IK0YGJ

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Maybe this isn't really what you are asking, but just in case, here it is: I like my Vibroplex, but my copy speed isn't very fast yet. Even with the weight all the way out, it is still too fast for me (I get myself in trouble sending faster than I can receive). I took apart an old telescoping antenna and found a section about 6 inches long that has the right I.D. to slide snugly over the end of the pendulum arm. I was then able to move the weight out past the dampener to slow down the bug. I am able to go down to about 10 wpm using this device. When my speed increases (my current speed is about 14 wpm, but my goal is to reach at least 20) I can remove the extension and go back to normal operation.

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